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Employee Benefit Plans (Narrative) (Detail) | 9 Months Ended
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Sep. 30, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Contributions to defined benefit pension plans and OPEB plans | $ 0
Expected contribution to voluntary employees' beneficiary association for the remainder of 2018 | 12,000,000
Dominion Energy Gas Holdings, LLC |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Contributions to defined benefit pension plans and OPEB plans | 0
Expected contribution to voluntary employees' beneficiary association for the remainder of 2018 | $ 12,000,000

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- Definition Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 + Details
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